Yieldable support



July 17, 1928.

R. D. PARKS YIELDABLE SUPPORT WITNESSES 5W Q Patented July 1.7, i928.

ROLAND DANE PARKS, 0F LAKE LINDEN, MICHIGAN.

YIELDABLE SUPPORT.

Application led. February 18, 1926. Serial No. 89,124.

The device of the present invention while capable of a wide field ofutility, is pri marily designed'for withstanding subsidence pressures insubterranean mining operations.

An object of the invention is to provide a. metal supportl or columnadapted to take the place of the supporting timbers usually employed.

A further object of the invention is to provide a yielding support ofthis character embodying a yieldable or strainable element which becomesdistorted under excessive pressures without distorting or twisting themain body of the column ory support.

A further object of the invention is to provide a device of the classdescribed which will be of rugged, durable, practical con struction,which will be highly `efiicient and capable of repeated use, and whichmay be manufactured with comparative economy.

In carrying out the invention I prefer to employ a plurality of metallicmembers capable of a relative sliding action when an intermediateyielding member is strained by pressures on the relatively movablemembers.

Preferably the strainable element is capableV of ready removal and,replacement so that undue pressures on the column can result inrendering useless onlyl the strainable element without impairing thefurther usefulness, or in any Way injuring the telescoping or relativelysliding members.

With the above noted and other objects in view, the invention consistsin certain novel features of construction and combinations andarrangements of parts, as will be more fully hereinafter set forth andpointed out in the claims. The invention may be more fully understoodfrom thev following description in connection with the accompanyingdrawings, wherein-` Fig. 1 is a broken view Vin front elevation of asupporting column embodying the invention.

Fig. 2 is a view in longitudinal section therethroughy on the line 2 2of Fig. 1.

Fig.l3 is a view in transverse section on the line 3-3 of Fig. 1. Y

Fig. 4 is a perspective view of the strainable element.

Figs. 5 and 6 are side elevational views of thecutting implements. V

Fig. 7 is an enlarged edge view ofthe element shown in Fig. 4.

The problems involved in withstanding the subsidence pressures insubterranean mining operations are too well recognizedto by a support of'ayieldable nature which I-Ience, the time kelement `is vital and can befurnished only will give underV excessive loadings, thereby allowing anatural arch to form and carry the greater portion of the subsidencepressure. Relatively non-yielding metallic supports, as they haveheretoforev been installed with rigidity and strength as the objectivebecome hopelessly deformed and vtwisted,blocl\. the undergroundpassageways,

and are difficult to remove after distortion.

In accordance with the present invention,

I provide a yieldable metallic column or strut in which the distortioncaused by subsidence pressures acts to telescope the column withoutdistorting any part thereof, except a strainable element which mayI bereadily removed and replaced.i

In thev accompanying ldrawings I have used the reference numeral 10 todesignate an I-beam which serves as the base of the column. A pair ofoppositely facing channel bars 11 are secured together in back toV backrelationship, the flanges 11a ofthe channels being accommodated betweenthe flanges or heads 1()a of the Ibeam. It will be noted that thechannel members 11 are vspaced apart for disposition upon the oppositesides of the I-beam. Preferablythe upper ends of both channel members 11are bolted to a spacer plate 12, and the upper portion of the I-beam 10which is received between the channel members may be supplemented byspacer plates 13, so that the channel members have a sliding fitron theI-beam. y

The-channel lmembers are provided with 'slots 14 and 15'` alignedrespectively with slots 16 and 17 in the I-beam. Bolts 18 'pass throughthe aligned slots 14, 16 and bolts 19 pass through the aligned slots 15,17, guide the relative sliding movement of the channel members and theI-beam. It will be noted that the slots 14 are relatively short, and theslots 16V relatively long, and also the slots 15 are relatively long,while the slots 17 are relatively short. However, the effective relantive sliding permitted by each set of slots is the same. By forming thechannel members and the I-beam each with a set of short slots,

and a set of long slots, l preservethe maxi-v able element is inthenature of a plate 2O of soft metal or ymetallic alloy which isinterposed'between the top of the '1l-beam 10 and a set of ltransverselymounted cutting tools 21 supported adjacent thereto by the upper ends ofthe channel members 11. It will be noted that the yieldable orstrainable member 20 isv formed with a plurality of grooves 22 eX-tending longitudinally thereof to provide relatively lthin weakenedportions 23 in the path 'of the cutting tools.

lvVlien the Vcolumn has been setup in a tunnel, and subsidence'pressuresbecome great i enough to overcome the friction between members 10 and11, plus the resistance offered by the ultimate. strength of the metalin the path of the cutting tools, there will be a relative slidingmovement or telcscoping action of the members 10 and '11. Cutting tools21 pass downwardly through the weakened portions 23 of the strainableelement 20, cuttingthrough these portions and cutting or extruding themetal therefrom. Slots 25 are provided in the channel bars for theescape of metal forced outwardly by the cutting tools.

. From the foregoing description it will be evident that l have providedfor considerable yielding of thecolumn without injury to any .portionthereof, except the member 20, so

that there is no danger of distorting the body of the column.Byidisassembling the sliding elements of the column, the strained.member 20 may be readily removed and replaced and the column reused. y

l have shown a strainableeleinent sub]eet Ato distortion undercompression,rbut it will be obvious that this element might be arrangedfor distortion when the column is erted on relatively rotatingmembers,and

that it also mightbe distortedfunder shearing strains or stresses.

lt will also be obvious that various types of supports embodying'theprinciple of the present invention may prove useful in other lfieldsrthan underground mining operations.

ln fact, devices embodying the invention are suitable "for use whereveryielding struts, trusses or braces are desirable. f

Various changes and alterations might be made in the general form andarrangement or" parts described, without 'departingfrom the invention.Hence I do not wish to limit myselfto the details set forth,'but sha-llconsider myself at Aliberty to'make such changes and alterations 'asfairly fall within `the spirit and scope of the appended claims. A

,l claimy 1. A support of the class describedincluding an I-beain,spaced 'oppositely facing channel members straddling the I-beamjandmounted for limited slidingmovement relative thereto, a metallic elementadapted to be f.

strained, vnormally blockingsliding move members straddling thej'Ib'eamanel'having.

limited sliding movement relative 'thereto,a soft metallicpl'ate'between thel channel members opposing-'sliding movementoff the'channel members relative to the *Iebeann and `eutting elementsI'associated with the channel members for strainingthe soft Imetal plateto permit such sliding movement;

. 3.' In a support 'of the class described, an I-beam, oppositely facingspaced channel members straddling the I-beam and :having limited slidingmovement relative thereto, a

soft metallicnplate between the `channel mem-V bers opposing'slidingmovement-of the .channel members relative tothe I-beam,'an'd cuttingelements associated with the ychannel members for straining` the .softmetalplate'to permit such sliding "movement,y said ysoft metal platevbeing formed with weakened portions in thepathA of movement of `saideut'- ting elements. p K

QA device of vthe class vdescribed in claim 2, and wherein the channelmembersfand I- beam are formedwith aligned slots, 'and bolts in saidslots guide the 'sliding movement'of the members.

ROLAND DANE lPaints.

